Building a new M4

[The Honey Badger]

Solid gun but many KWA only parts. I own a KM4 and love the way it inaccurately spits BB's.

[Charlie Zulu]

Just grab any MP7 on the market and you're good! Man I love those things...

In all seriousness though, my little brother and his friends all have KWA SR-10s. I constantly hear them complaining about having to buy KWA brand mags, buckings, etc. You're basically stuck with their parts, and I've never been one to advocate proprietary components. Back in the day when I was first starting out I had a CA CAR-15. I put almost 30,000 rounds through it before the gearbox had a heart attack and gave out.

If you don't have a problem with proprietary parts that limit your upgrade options, go with a KWA. If you do, go with a CA. Either way they need a good 6.03mm barrel, but not longer than about 400mm or the type 1 cylinder won't be able to push out enough air to take advantage of it. Firefly hop up buckings have also worked wonders for me in the past. Highly recommended upgrade if you can find one.